Tug-of-war over TCE risks intensifies

The battle over whether the US Environmental Protection Agency should consider fetal heart defects in its evaluation of the health risks of trichloroethylene (TCE) is heating up. A coalition of environmental groups and an internal EPA email claim that political interference from the Trump administration prompted the EPA to ignore such effects in its TCE risk evaluation finalized Nov. 23. The chemical industry counters that the science does not support the EPA’s use of TCE’s cardiac effects in risk determination.

TCE is one of the first 10 chemicals the EPA evaluated under 2016 revisions to the Toxic Substances Control Act (TSCA). The agency found that dozens of uses pose unreasonable health risks to workers and consumers. Those uses include TCE as an intermediate in manufacturing refrigerants, as a degreasing solvent, and as an ingredient in adhesives, greases, paints, and cleaners.

The EPA based its risk determination on TCE’s immunological effects, which occur at lower concentrations than its carcinogenic, neurological, and developmental effects. Environmental groups are pushing the EPA to base its evaluation of TCE on fetal heart malformations, which they say occur at even lower levels than immunological effects.

In a Feb. 26 letter to the EPA, Safer Chemicals Healthy Families and other environmental groups claim that the agency underestimated the risks of TCE because of political interference by the Trump administration. “White House staff directed EPA career scientists to alter the draft evaluation so that the most sensitive endpoint—fetal heart malformations—was no longer used to determine TCE’s risks to health,” the groups say.

C&EN obtained an internal EPA email that corroborates the claim of White House interference. The email was sent on March 10 to staff in the office that implements TSCA from the acting head of that office, Michal Freedhoff. The EPA recently withdrew its evaluation of perfluorobutanesulfonic acid (PFBS) for similar reasons.

Stephen Risotto, senior director at the American Chemistry Council, which represents chemical manufacturers, responded with a March 16 letter to the EPA, noting that the EPA’s chemical advisory committee and the National Academies confirmed that there is insufficient evidence of cardiac effects to justify their use in evaluating the risks of TCE. If the EPA decides to further review such effects, “we urge you to commission an independent review panel with the appropriate expertise to ensure the transparency and objectivity of the process,” Risotto writes.